Chronic knee pain can be caused by injuries, mechanical problems, types of arthritis and other problems. Some of the most common problems are sprained ligaments, meniscus tears, tendinitis, and runner's knee. If you have an old knee injury that wasn’t properly treated, it may flare up now and then or hurt all the time.

Osteoarthritis is a wear-and-tear condition that occurs when the cartilage in your knee deteriorates with use and age. Rheumatoid arthritis. The most debilitating form of arthritis, rheumatoid arthritis is an autoimmune condition that can affect almost any joint in your body, including your knees. Although rheumatoid arthritis is a chronic disease, it tends to vary in severity and may even come and go.

Knee bursitis, some knee injuries cause inflammation in the bursae, the small sacs of fluid that cushion the outside of your knee joint so that tendons and ligaments glide smoothly over the joint.

Patellar tendinitis. Tendinitis is irritation and inflammation of one or more tendons — the thick, fibrous tissues that attach muscles to bones. Runners, skiers, cyclists, and those involved in jumping sports and activities are prone to develop inflammation in the patellar tendon, which connects the quadriceps muscle on the front of the thigh to the shinbone.

Torn meniscus. The meniscus is formed of tough, rubbery cartilage and acts as a shock absorber between your shinbone and thighbone. It can be torn if you suddenly twist your knee while bearing weight on it.

Hip or foot pain. If you have hip or foot pain, you may change the way you walk to spare these painful joints. But this altered gait can place more stress on your knee joint. In some cases, problems in the hip or foot can refer pain to the knee.

Chronic hip pain is a pain in your hip that has lasted longer than six weeks. the most common causes are:

• Osteoarthritis, where the hip joint is worn away in parts. The hip joint is a ball and socket joint. A healthy hip joint has a smooth socket and the ball glides around the socket easily allowing you to move your hip without pain. If your hip is arthritic, then the surface of the socket becomes uneven. As a result, movement is impaired and eventually the surface will become inflamed causing arthritic hip pain. Diagnosis of osteo-arthritic hip pain is made by x-ray imaging.
• Bursitis, where a cushion of fluid in your hip joint becomes inflamed and painful. In order to stop bone rubbing on bone between the ball and socket of your hip, there is a cushion of fluid between them. Sometimes this cushion gets inflamed due to poor movement techniques or as a sign of early stages of wear and tear. This inflammation causes pain.

Referral pain from the lower back, where a nerve in your back is impinged or trapped causing a referral of pain into the hip. Iliotibial band syndrome, where a band of tissue on the outside of your thigh becomes inflamed and sore. This is due to tightness in the band and its surrounding muscles which can result in the band being repetitively strained. Over time causes inflammation and pain.

Flat feet, this is where your feet are flatter than they should be! Orthotic correction and strength exercises work well for this complaint.

Piriformis syndrome is where your piriformis muscle in your buttock gets tight and inflamed causing pain.

The four most common causes of shoulder pain and disability in primary care are rotator cuff disorders, glenohumeral disorders, acromioclavicular joint disease and referred neck pain.

Subacromial impingement is the most common source of shoulder pain. There may be a history of heavy lifting or repetitive movements, especially above shoulder level. However, it often occurs in the non-dominant arm and in non-manual workers.

A rotator cuff tear, usually follows trauma in young people. It is usually atraumatic in elderly people and caused by attrition from bony spurs on the undersurface of the acromion or intrinsic degeneration of the cuff, possibly.

Glenohumeral disorders "Adhesive capsulitis" most often presents between the ages of 40 to 65 years, whereas osteoarthritis is most common in those aged 60 years or older. Adhesive capsulitis (frozen shoulder) and arthritis often present with a history of non-adhesive capsulitis symptoms, cause deep joint pain and restrict activities such as putting on a jacket . Adhesive capsulitis is more common in people with diabetes and may also occur after prolonged immobilisation. There is usually generalised shoulder pain and a restriction of passive and active movements.

Acromioclavicular disorders are usually caused by trauma or osteoarthritis. Pain and tenderness are localised to the acromioclavicular joint and there is a restriction of passive, horizontal movement of the arm across the body when the elbow is extended. Acromioclavicular osteoarthritis may cause subacromial impingement.

Referred neck pain, typically presents with pain and tenderness of the lower neck and suprascapular area, with pain referred to the shoulder and upper arm. There may be a restriction of shoulder movement and movement of the neck and shoulder may reproduce more generalised upper back, neck and shoulder pain.